Huang Bin, Gu Hangkun, Xiao Kang, Qu Fangshu, Yu Huarong, Wei Chunhai
Department of Municipal Engineering, School of Civil Engineering, Guangzhou University, Guangzhou 510006, China.
Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou 510006, China.
Membranes (Basel). 2020 Jul 10;10(7):149. doi: 10.3390/membranes10070149.
Membrane fouling is still the bottleneck affecting the technical and economic performance of the ultrafiltration (UF) process for the surface water treatment. It is very important to accurately understand fouling mechanisms to effectively prevent and control UF fouling. The rejection performance and fouling mechanisms of the UF membrane for raw and coagulated surface water treatment were investigated under the cycle operation of constant-pressure dead-end filtration and backwash. There was no significant difference in the UF permeate quality of raw and coagulated surface water. Coagulation mainly removed substances causing turbidity in raw surface water (including most suspended particles and a few organic colloids) and thus mitigated UF fouling effectively. Backwash showed limited fouling removal. For the UF process of both raw and coagulated surface water, the fittings using single models showed good linearity for multiple models mainly due to statistical illusions, while the fittings using combined models showed that only the combined complete blocking and cake layer model fitted well. The quantitative calculations showed that complete blocking was the main reason causing flux decline. Membrane fouling mechanism analysis based on combined models could provide theoretical supports to prevent and control UF fouling for surface water treatment.
膜污染仍然是影响地表水超滤（UF）处理工艺技术和经济性能的瓶颈。准确理解污染机制对于有效预防和控制超滤污染非常重要。在恒压死端过滤和反洗的循环操作下，研究了超滤膜对原水和混凝后地表水的截留性能及污染机制。原水和混凝后地表水的超滤渗透水质没有显著差异。混凝主要去除了原地表水中导致浊度的物质（包括大多数悬浮颗粒和一些有机胶体），从而有效减轻了超滤污染。反洗的去污效果有限。对于原水和混凝后地表水的超滤过程，单一模型拟合显示多种模型具有良好的线性关系，这主要是由于统计错觉，而组合模型拟合表明只有组合的完全堵塞和滤饼层模型拟合良好。定量计算表明，完全堵塞是通量下降的主要原因。基于组合模型的膜污染机制分析可为地表水超滤处理中预防和控制膜污染提供理论支持。
